Unreactive metals such as gold are found in the Earth in an uncombined state, but most metals are found as compounds that require chemical reactions to extract the metal.
Ores are naturally occurring rocks that provide an economic starting point for the manufacture of metals.
Metals that are less reactive than carbon can be extracted from their oxides by reduction with carbon. Iron and lead can be extracted in this way.
Iron oxide (Fe2O3) and coke (carbon) are heated in the blast furnace to produce iron. The coke burns to produce carbon dioxide and this reaction heats up the furnace (exothermic reaction):
The carbon dioxide reacts with the coke to produce carbon monoxide:
When heated, the iron oxide reacts with the carbon monoxide to produce iron. Iron oxide is reduced and carbon monoxide is oxidised:
This can also be done with lead oxide in the lab:
